JP2021018213A - Water repellency detector - Google Patents

Abstract

To provide a water repellency detector capable of detecting water repellency with a simple configuration.SOLUTION: An on-vehicle controller 20 has a water repellency determining unit 23 that determines the degree of water repellency of glass based on the transition of a speed of a vehicle 100 and an amount of raindrops. The on-vehicle controller 20 determines that the degree of water repellency is high when the decrease in the amount of raindrops increases as the speed of the vehicle 100 increases. A movement amount of raindrops 11a can be acquired from the transition of the amount of raindrops detected by a rain sensor 12. That is, while the vehicle 100 is traveling at high speed, the greater the decrease in the amount of raindrops is, the greater the amount of movement is. Therefore, the on-vehicle control device 20 determines that the degree of water repellency is high when the decrease in the amount of raindrops increases as the speed of the vehicle 100 increases.SELECTED DRAWING: Figure 4

Description

The disclosure herein relates to a water repellency detector that detects water repellency in vehicle glass.

Conventionally, a wiper device has been disclosed that detects the amount of raindrops adhering to the windshield of a vehicle based on the amount of light reflected on the windshield and controls the drive of the wiper blade according to the detected amount of raindrops (for example). See Patent Document 1). The raindrop detection device described in Patent Document 1 detects the presence or absence of water repellency on the outer surface of the windshield, and controls the operation of the wiper device according to the presence or absence of water repellency.

Japanese Unexamined Patent Publication No. 2014-133426

The raindrop detecting device described in Patent Document 1 includes two raindrop detecting means. Each raindrop detecting means is adjusted so that the amount of reflection due to raindrops differs depending on whether there is water repellency or water repellency, and the presence or absence of water repellency is determined based on the difference in the amount of reflection for a certain period of time. There is.

However, the raindrop detecting device of Patent Document 1 requires two raindrop detecting means, and has a problem that the number of parts increases and the physique increases.

Therefore, the object of disclosure is made in view of the above-mentioned problems, and an object of the present invention is to provide a water repellency detecting device capable of detecting water repellency with a simple configuration.

The present disclosure employs the following technical means to achieve the aforementioned objectives.

The water repellency detecting device disclosed here is a water repellency detecting device for detecting the water repellency of the windshield (11) of the vehicle (100), and obtains the amount of raindrops adhering to the outer surface of the windshield. A water repellency determination unit (23) that determines the degree of water repellency of the windshield based on the transition of the acquired raindrop amount and the vehicle speed, and the speed acquisition unit (20) that acquires the speed of the vehicle. ), And the water repellency determination unit determines that the degree of water repellency is high when the decrease in the amount of raindrops increases as the speed of the vehicle increases.

According to such a water repellency detecting device, the degree of water repellency of the windshield is determined by the water repellency determining unit based on the transition of the vehicle speed and the amount of raindrops. When raindrops have high water repellency, they easily move on the windshield surface due to gravity and wind. Therefore, when the water repellency is high, the amount of movement of raindrops increases due to the wind speed due to traveling as the speed of the vehicle increases. On the contrary, when the water repellency is low, the amount of movement is small because raindrops are difficult to move even if the speed of the vehicle is increased. Such a moving amount of raindrops can be acquired by the transition of the amount of raindrops detected by the raindrop amount acquisition unit. That is, while the vehicle is traveling at high speed, the greater the amount of raindrops that decrease, the greater the amount of movement. Therefore, the water repellency determining unit determines that the degree of water repellency is high when the decrease in the amount of raindrops increases as the speed of the vehicle increases. Therefore, the water repellency can be detected with high accuracy by using the transition of the amount of raindrops. In such a water repellency detection device, the physical configuration is mainly composed of one type of light amount detection unit, and the raindrop amount acquisition unit, the speed acquisition unit, and the water repellency determination unit are realized by an arithmetic processing unit or the like. Therefore, water repellency can be detected with a simple structure.

Further, the water repellency detecting device disclosed here is a water repellency detecting device for detecting the water repellency of the windshield (11) of the vehicle (100), and includes an imaging unit (60) for imaging the windshield and an imaging unit (60). The water repellency determination unit (23) that determines the degree of water repellency of the windshield based on the shape of the raindrops is included, and the water repellency determination unit is such that the shape of the raindrops in the captured image is closer to a circular shape. , Judged as having high water repellency.

According to such a water repellency detecting device, the degree of water repellency of the windshield is determined by the water repellency determining unit based on the shape of the raindrop. The shape of raindrops is close to a circular shape when the water repellency is high. Therefore, when the water repellency is high, the shape of the raindrop is close to a circular shape, and conversely, when the water repellency is low, the shape of the raindrop is close to a shape different from the circular shape. The shape of such raindrops can be acquired from the image captured by the imaging unit. Therefore, the water repellency determining unit determines that the closer the shape of the raindrops in the captured image is to a circular shape, the higher the water repellency. Therefore, the water repellency can be detected with high accuracy by using the shape of the raindrop. In such a water repellency detecting device, the physical configuration is mainly composed of one type of imaging unit, and the water repellency determining unit is realized by an arithmetic processing unit or the like. Therefore, water repellency can be detected with a simple structure.

The reference numerals in parentheses of the above-mentioned means are examples showing the correspondence with the specific means described in the embodiments described later.

The perspective view which shows the vehicle 100. The block diagram which shows the electric structure of the vehicle-mounted control device 20 in a simplified manner. The cross-sectional view which shows the vehicle-mounted detection device 10. The figure explaining the relationship between water repellency and the behavior of raindrop 11a. The figure explaining the behavior of the raindrop 11a at the time of traveling. The figure explaining the relationship between water repellency and the amount of raindrops. An example of a map for determining the water repellency level based on the decrease and velocity of the raindrop signal. The figure which shows the vehicle-mounted detection device 10A of the 2nd Embodiment. The figure explaining the relationship between water repellency and the behavior of raindrop 11a.

Hereinafter, embodiments for carrying out the present disclosure with reference to the drawings will be described using a plurality of embodiments. In each embodiment, the same reference mark may be added to the portion corresponding to the matter described in the preceding embodiment, or one character may be added to the preceding reference code to omit the duplicated description. When a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those in the previously described embodiment. In addition to the combination of the parts specifically described in each embodiment, it is also possible to partially combine the embodiments as long as the combination does not cause any trouble.

(First Embodiment)
The first embodiment of the present disclosure will be described with reference to FIGS. 1 to 7. The vehicle-mounted detection device 10 of the present embodiment integrates, for example, a rain sensor 12 that detects raindrops 11a adhering to the windshield 11 of the vehicle 100 and a solar radiation sensor 13 that detects the amount of solar radiation around the vehicle 100. is there. As shown in FIG. 1, the vehicle-mounted detection device 10 is installed on the vehicle interior side of the windshield 11.

As shown in FIG. 2, the vehicle-mounted detection device 10 communicates with the vehicle-mounted control device 20. The vehicle-mounted control device 20 controls a control target, for example, a wiper device 30 based on signals from the vehicle-mounted detection device 10 and each unit.

First, the vehicle-mounted detection device 10 will be described. The in-vehicle detection device 10 includes a rain sensor 12, a solar radiation sensor 13, a cover housing 14, a circuit board 15, and a control unit 16. The rain sensor 12 includes a light emitting element 41, a light receiving element 42, and a light guide lens unit 43. Further, the solar radiation sensor 13 includes a solar radiation detection element 51 and a solar light guide unit 52.

The cover housing 14 has the appearance of the vehicle-mounted detection device 10. The cover housing 14 is a housing for accommodating the rain sensor 12, the solar radiation sensor 13, the circuit board 15, and the control unit 16. The cover housing 14 is made of a metal material or a resin material. The plan shape of the cover housing 14 as viewed from the opening end side to the bottom surface side is, for example, a quadrangular shape.

Further, the cover housing 14 is attached to a bracket 17 fixed to the windshield 11. As a result, the cover housing 14 and the bracket 17 form an accommodating body. The bracket 17 is, for example, a metal plate pressed into a predetermined shape, and is fixed to the windshield 11 with an adhesive or the like.

The circuit board 15 is mounted with the light emitting element 41 and the light receiving element 42 of the rain sensor 12 and the solar radiation detecting element 51 of the solar radiation sensor 13. The circuit board 15 has a plate shape, for example, a printed circuit board.

Further, the circuit board 15 is mounted with the connector 18 and the control unit 16. The connector 18 is a resin connection component to which a wiring connector (not shown) is connected. The connector 18 has a terminal 18a that is electrically connected to a circuit formed on the circuit board 15. The terminal 18a is insert-molded into the connector 18. The circuit board 15 is housed on the bottom surface side (upper side of FIG. 3) of the cover housing 14 with the lower side of FIG. 3 facing the open end of the cover housing 14.

The control unit 16 executes a program stored in the storage medium and controls each unit. The control unit 16 calculates the amount of raindrops and the amount of solar radiation based on the outputs of the rain sensor 12 and the solar radiation sensor 13. The control unit 16 transmits the calculated amount of raindrops and the amount of solar radiation to the vehicle-mounted control device 20 via the connector 18. In the control unit 16, the plurality of electronic components are composed of, for example, an IC, a resistance element, a chip capacitor, and the like.

Next, the rain sensor 12 will be described. The rain sensor 12 is a raindrop 11a detecting device configured to detect raindrops 11a adhering to the windshield 11 of the vehicle 100. The in-vehicle detection device 10 is a combination of the rain sensor 12 and the solar radiation sensor 13.

The light emitting element 41 is a light emitting device that irradiates a predetermined detection area 22 with measurement light for detecting raindrops 11a adhering to the windshield 11. The detection area 22 has a size sufficiently smaller than that of the windshield 11. The size of the detection area 22 is smaller than, for example, the size of the rearview mirror projected onto the windshield 11. The light emitting element 41 is realized by, for example, a light emitting diode (LED) that emits light toward the windshield 11. The control unit 16 functions as a drive circuit for driving the light emitting diode. The control unit 16 controls the light emitting diode by PWM control, for example. The control unit 16 blinks the light emitting diode by the pulse signal.

The light receiving element 42 is a light receiving device that receives light reflected by the detection area 22 of the windshield 11. The light receiving element 42 is realized by, for example, a photodiode (PD) that detects the intensity of the received light. The control unit 16 functions as a processing circuit that amplifies the signal of the photodiode. The light receiving element 42 is mounted on one surface of the circuit board 15 at a predetermined distance from the light emitting element 41.

The light guide lens unit 43 is configured to guide the light emitted from the light emitting element 41 to the windshield 11 and the light reflected by the windshield 11 to the light receiving element 42. The light guide lens portion 43 is housed in the cover housing 14. The light guide lens unit 43 includes a first lens unit 44 and a second lens unit 45.

The first lens unit 44 is a portion of the light guide lens unit 43 that collects the light of the light emitting element 41. The first lens unit 44 faces the light emitting element 41. The second lens portion 45 is a portion that collects the reflected light reflected by the windshield 11 on the light receiving element 42. The second lens unit 45 faces the light receiving element 42.

With such a configuration, the light emitted from the light emitting element 41 is guided to the windshield 11 via the first lens portion 44 and is reflected by the windshield 11. Further, the light reflected by the windshield 11 is guided to the light receiving element 42 via the second lens portion 45. When the raindrop 11a adheres to the windshield 11, the refraction characteristic of the light in the windshield 11 changes, so that the intensity of the light detected by the light receiving element 42 changes. Therefore, the rain sensor 12 can detect that the raindrop 11a has adhered to the windshield 11 based on the intensity of the light received by the light receiving element 42.

The control unit 16 calculates the amount of raindrops adhering to the windshield 11 based on the detection signal output from the light receiving element 42. When the raindrop 11a is not attached to the detection area 22, the measurement light emitted from the light emitting element 41 travels as shown by the solid arrow in FIG. 3, and most of it is reflected by the windshield 11. , The light is received by the light receiving element 42. However, when the raindrop 11a is attached to the detection area 22, a part of the measurement light emitted from the light emitting element 41 is passed through the raindrop 11a attached to the detection area 22 and is indicated by the broken line arrow in FIG. As shown by, the light is emitted to the outside of the windshield 11, so that the amount of light received by the light receiving element 42 is reduced. As the amount of raindrops adhering to the detection area 22 increases, the amount of light emitted to the outside of the windshield 11 increases, and the amount of light received by the light receiving element 42 decreases. Thereby, the amount of raindrops 11a adhering to the detection area 22 can be detected based on the amount of light received by the light receiving element 42. Therefore, the larger the amount of raindrops adhering to the detection area 22, the smaller the detection signal of the rain sensor 12, and the smaller the amount of raindrops adhering to the detection area 22, the larger the detection signal of the rain sensor 12. The control unit 16 converts the detection signal into a raindrop amount signal corresponding to the raindrop amount, and outputs the converted calculation result to the vehicle-mounted control device 20. The raindrop amount signal has a format in which the value increases as the amount of raindrop increases.

Next, the solar radiation sensor 13 will be described. The solar radiation sensor 13 detects the amount of solar radiation. The solar radiation detection element 51 constituting the solar radiation sensor 13 detects the amount of solar radiation by receiving the solar radiation incident on the windshield 11. Such a solar radiation detection element 51 is realized by, for example, a photodiode (PD) that detects the intensity of the received light. The control unit 16 functions as a processing circuit that acquires the amount of solar radiation based on the signal of the photodiode. The solar radiation detection element 51 is arranged between the light emitting element 41 and the light receiving element 42 of the rain sensor 12 on one surface of the circuit board 15.

The solar light guide unit 52 guides the solar light incident on the windshield 11 in a predetermined elevation angle range to the solar radiation detecting element 51. The solar light guide unit 52 is housed in the cover housing 14 so as to face the solar radiation detecting element 51. The solar light guide unit 52 is arranged between the first lens unit 44 and the second lens unit 45, and is integrally formed with the first lens unit 44 and the second lens unit 45.

With such a configuration, the light introduced into the solar light guide unit 52 is guided to the solar radiation detecting element 51. When the amount of solar radiation is large, the detection signal of the solar radiation detection element 51 becomes large. Therefore, the control unit 16 detects the amount of solar radiation based on the detection signal received by the solar radiation detection element 51. The control unit 16 converts the detection signal into a solar radiation amount signal corresponding to the solar radiation amount and outputs the detection signal to the in-vehicle control device 20. The solar radiation signal has a format in which the value increases as the amount of solar radiation increases.

The solar light guide portion 52 is integrally molded with the light guide lens portion 43. Therefore, one lens is composed of the light guide lens unit 43 and the solar light guide unit 52. This lens is housed in the cover housing 14 so as to be located on the windshield 11 side away from the circuit board 15. Further, the side of the lens opposite to the side on which the first lens portion 44, the second lens portion 45, and the solar light guide portion 52 are formed has a planar shape.

Further, as shown in FIG. 3, a sheet 19 is attached to the flat portion of the lens. The sheet 19 is in contact with not only the light guide lens portion 43 but also the windshield 11. The light guide lens unit 43 takes in light from the windshield 11 via the sheet 19.

Next, the wiper device 30 will be described with reference to FIGS. 1 and 2. The wiper device 30 operates the wiper to wipe off the raindrops 11a adhering to the windshield 11 according to the operating position of the wiper switch 31. When the wiper device 30 is in the automatic control mode (AUTO mode), the vehicle-mounted control device 20 controls the wiper operation start timing and the wiper operation interval based on the signal acquired from the vehicle-mounted detection device 10.

As shown in FIG. 1, the wiper device 30 includes a wiper switch 31, a wiper motor 32, a wiper blade 33, and a link mechanism 34. The wiper motor 32 is a drive source that generates a driving force. The link mechanism 34 converts the drive torque generated by the wiper motor 32 into reciprocating motion and transmits it to the wiper blade 33 to reciprocate the wiper blade 33. The wiper blade 33 performs a reciprocating wiping operation on the windshield 11. The reciprocating wiping operation of the wiper blade 33 is executed by outputting a drive instruction signal from the vehicle-mounted control device 20 to the wiper motor 32.

The wiper switch 31 is installed in the driver's seat in the automobile, and stops the reciprocating wiping operation of the wiper blade 33 (OFF mode), automatic control (AUTO mode), low speed operation (LO mode), and high speed operation (HI mode). , Has a switch function to switch by manual operation of the driver. One of these operation modes is selected by rotating the wiper switch 31 to, for example, any one of the four operation positions. Then, when one of the four operation modes described above is selected, the wiper switch 31 outputs information about the selected operation mode to the vehicle-mounted control device 20.

The in-vehicle control device 20 executes a program stored in the storage medium and controls each unit. The in-vehicle control device 20 has at least one arithmetic processing unit (CPU) and a storage medium for storing programs and data. The in-vehicle control device 20 is realized by, for example, a microcomputer having a storage medium readable by a computer. A storage medium is a non-transitional substantive storage medium that stores computer-readable programs and data non-temporarily. The storage medium is realized by a semiconductor memory, a magnetic disk, or the like.

The in-vehicle control device 20 receives sensor signals from various sensors of the vehicle 100. In addition to the above-mentioned vehicle-mounted detection device 10, the various sensors include, for example, an engine water temperature sensor, a vehicle speed sensor 21, an outside air temperature sensor, and an indoor temperature sensor. The in-vehicle control device 20 controls each unit based on the acquired sensor signal and the operation signal of each unit. Therefore, the in-vehicle control device 20 also functions as a raindrop amount acquisition unit that acquires the amount of raindrops from the in-vehicle detection device 10, and also functions as a speed acquisition unit that acquires the speed of the vehicle 100 from the vehicle speed sensor 21.

The in-vehicle control device 20 has a function as a water repellency detecting device for detecting the water repellency of the windshield 11. Specifically, the in-vehicle control device 20 has a water repellency determining unit 23 that determines the degree of water repellency of the windshield 11 based on the transition of the speed and the amount of raindrops of the vehicle 100.

As shown in FIG. 4, the behavior of the raindrop 11a adhering to the detection area 22 differs depending on whether the water repellency is high or low. When the water repellency is high and the speed of the vehicle 100 is high, the raindrop 11a moves from the detection area 22 in a short time, but when the water repellency is low, the raindrops move to the detection area 22 even if the speed of the vehicle 100 is high. The time that 11a stays becomes longer.

Further, as shown in FIG. 5, even if the water repellency is high, the raindrop 11a stays in the detection area 22 for a long time when the vehicle is stopped, but the raindrop 11a moves easily from the detection area 22 due to the running wind during traveling. When the raindrop 11a receives the running wind, if it has high water repellency, it moves upward along the surface of the windshield 11.

Further, as shown in FIG. 6, the raindrop amount signal, that is, the detection signal of the light receiving element 42 changes with the passage of time. In heavy rain, poor water repellency will increase the raindrop signal over time. If the water repellency is low, the raindrop 11a is difficult to move from the detection area 22, so that the raindrop amount signal increases. Then, when the wiper device 30 operates, the raindrop amount signal becomes zero again.

On the other hand, when the amount of raindrops is large, if the water repellency is high, the amount of raindrop signal increases with time but may decrease temporarily. This is because if the water repellency is high, the raindrop 11a moves from the detection area 22, so that the raindrop amount signal does not always increase. Then, when the wiper device 30 operates, the raindrop amount signal becomes zero again.

Similarly, in the case of less rain, if the water repellency is low, the raindrop amount signal will increase over time, but the degree of increase will be less than in the case of heavy rain. When there is little rain, if the water repellency is high, the raindrop amount signal will repeatedly increase and decrease over time, and the degree of increase will be less than when there is a lot of rain.

As described above, there is a correlation between the water repellency and the transition of the raindrop amount signal, and the speed of the vehicle 100 is also a factor for determining the degree of water repellency. The water repellency determination unit 23 determines, for example, the degree of water repellency at a plurality of levels, and evaluates the degree of water repellency, for example, in four stages of levels 1 to 4. The higher the level, the higher the water repellency, and the lower the level, the lower the water repellency. Therefore, level 4 has the highest water repellency, and level 1 has the lowest water repellency.

The water repellency determination unit 23 determines the level of water repellency using, for example, a control map as shown in FIG. The water repellency determination unit 23 determines the level of water repellency using the speed of the vehicle 100 and the amount of decrease in the raindrop amount signal. The amount of decrease in the raindrop amount signal is the total amount of decrease in the amount of raindrop amount signal per unit time. For example, in the case of FIG. 6, the amount of reduction is Δm1 + Δm2.

The in-vehicle control device 20 receives a signal from the wiper switch 31 and outputs a drive instruction signal corresponding to the signal to the wiper motor 32. That is, when the positions selected by the wiper switch 31 are the stop (OFF mode) position, the low speed operation (LO mode) position, and the high speed operation (HI mode) position of the wiping operation, the in-vehicle control device 20 is used. The wiper motor 32 is driven and controlled so as to execute the wiping mode. The wiping mode is a control mode in which the interval time of the reciprocating wiping operation of the wiper blade 33 is different. The stop mode, low speed mode and high speed mode are also selected by the user. The rotation speed of the motor, that is, the moving speed of the wiper blade 33 is different between the low speed mode and the high speed mode. The movement speed of the wiper blade 33 is faster in the high-speed mode than in the low-speed mode, and the interval time of the reciprocating wiping operation is shorter.

When the wiper switch 31 is operated in the automatic control mode (AUTO mode), the vehicle-mounted control device 20 determines the wiping mode related to the wiping operation of the wiper blade 33 based on the amount of raindrops, the water repellency level, and the vehicle speed. Then, the in-vehicle control device 20 outputs a drive signal to the wiper motor 32 based on the determination result. In the wiping mode, the interval time is, for example, 7 seconds, 5 seconds, 3 seconds, 2 seconds, 1.5 seconds, and 0.5 seconds in order from the longest interval.

The wiping mode is selected based on the detected amount of raindrops, but even if the amount of raindrops is the same, if the water repellency level is high and the vehicle speed is high, the need for wiping operation is reduced, so the interval time should be increased. Set it long, for example 7 seconds. Even if the amount of raindrops is the same, if the water repellency level is low, even if the vehicle speed is high, the wiping operation is highly necessary, so the interval time is set short, for example, 3 seconds.

When the water repellency level is low, for example, the water repellency is determined to be level 1, the in-vehicle control device 20 controls to inject a water repellency washer liquid in order to restore the water repellency. The water-repellent washer fluid has the ability to impart water repellency and is stored in the washer tank. Although not shown, the washer tank is mounted in, for example, the engine room of the vehicle 100. Then, the washer fluid in the washer tank is sucked by the washer pump, pressurized and injected. The in-vehicle control device 20 injects the water-repellent washer fluid by controlling the washer pump.

Further, the water repellency determining unit 23 may correct the amount of raindrops detected by the rain sensor 12 according to the water repellency level. Even if the amount of raindrops is the same, the amount of raindrops adhering to the detection area 22 changes depending on the water repellency level. When the water repellency level is high, the raindrop 11a is difficult to spread in the detection area 22, so that the contact area between the windshield 11 and the raindrop 11a becomes small. Therefore, when the water repellency level becomes high, the detection signal may become small even if the amount of raindrops is the same. Therefore, an appropriate amount of raindrops can be obtained by correcting the amount of raindrops detected by the rain sensor 12 according to the water repellency level.

Further, the in-vehicle control device 20 stores the date and time when the water repellency was applied. The date and time when the water repellency is imparted is the date and time when the water repellent washer liquid is sprayed, or the date and time when the water repellent coating film is applied at a maintenance shop or the like during maintenance of the vehicle 100. The date and time of application of the water-repellent washer fluid is automatically stored in the vehicle-mounted control device 20. The date of construction is input by the driver or the builder.

Further, the in-vehicle control device 20 records the wiping operation time of the wiper from the date and time of application. The in-vehicle control device 20 records the wiping operation time for each wiping mode. When the wiping operation time becomes long, the coating film on the windshield 11 gradually deteriorates, and the water repellency level decreases. Further, as the number of wiping operations increases, the coating film on the windshield 11 gradually decreases, and the water repellency level decreases. By recording the wiping operation time for each wiping mode, the number of wiping operations can be calculated. Therefore, the water repellency level is corrected based on the wiping operation time from the date and time of application. This makes it possible to reduce erroneous determination of the water repellency level. For example, if the water repellency level is determined to be level 1 even though the time from the grant date and time is short, there is a risk of failure of the vehicle-mounted detection device 10. Therefore, the water repellency level can be determined by combining with other detected values.

As described above, the in-vehicle control device 20 of the present embodiment has a water repellency determining unit 23 that determines the degree of water repellency of the glass based on the transition of the speed and the amount of raindrops of the vehicle 100. Then, the in-vehicle control device 20 determines that the degree of water repellency is high when the decrease in the amount of raindrops increases as the speed of the vehicle 100 increases. If the raindrop 11a has high water repellency, it easily moves on the glass surface due to gravity, wind, or the like. Therefore, when the water repellency is high, as the speed of the vehicle 100 increases, the amount of movement of the raindrop 11a increases due to the wind speed due to traveling. On the contrary, when the water repellency is low, even if the speed of the vehicle 100 is increased, the raindrop 11a is difficult to move, so that the amount of movement is small. The amount of movement of the raindrop 11a can be obtained from the transition of the amount of raindrop detected by the rain sensor 12. That is, while the vehicle 100 is traveling at high speed, the greater the amount of raindrops that decrease, the greater the amount of movement. Therefore, the in-vehicle control device 20 determines that the degree of water repellency is high when the decrease in the amount of raindrops increases as the speed of the vehicle 100 increases. As a result, the water repellency can be detected with high accuracy by using the amount of movement of the raindrop 11a.

Since the rain sensor 12 is the main physical configuration of the water repellency determining unit 23 of the vehicle-mounted control device 20, the water repellency determining unit 23 can be mounted without changing the physical configuration from the existing rain sensor 12. Therefore, water repellency can be detected with a simple structure.

Further, in the present embodiment, the light emitting element 41 is used as an irradiation unit that irradiates light toward the inner surface of the windshield 11, and the light amount acquisition unit that acquires the amount of reflected light of the light that is emitted toward the inner surface of the windshield 11. A light receiving element 42 is provided. Then, the control unit 16 calculates the amount of raindrops adhering to the outer surface of the windshield 11 based on the amount of light acquired by the light receiving element 42. Therefore, the control unit 16 functions as a raindrop amount calculation unit. Since the amount of raindrops is optically detected in this way, the rain sensor 12 can be realized with a simple configuration.

Further, in the present embodiment, the detected water repellency level is used for controlling the wiper device 30 and controlling the injection of the washer fluid, but is not limited to such control. For example, the detected water repellency level may be displayed to notify the driver of the decrease in the water repellency level.

(Second Embodiment)
Next, the second embodiment of the present disclosure will be described with reference to FIGS. 8 and 9. The present embodiment is characterized in that the vehicle-mounted detection device 10A is a camera type. In the first embodiment described above, the vehicle-mounted detection device 10 uses the measurement light from the light emitting element 41, but in the present embodiment, the image pickup unit 60 is used to determine the water repellency.

Specifically, the vehicle-mounted detection device 10A includes an imaging unit 60. The imaging unit 60 is installed on the vehicle interior side of the windshield 11 and images the detection area 22 of the windshield 11. The image capturing unit 60 transmits the captured image data to the vehicle-mounted control device 20.

The in-vehicle control device 20 determines the amount of raindrops based on the captured image. For example, the in-vehicle control device 20 calculates the area occupied by the raindrops 11a in the captured image per unit time, and determines that the amount of raindrops increases as the area increases.

Further, the in-vehicle control device 20 acquires the shape of the raindrop 11a based on the captured image. Then, the in-vehicle control device 20 determines that the closer the shape of the acquired raindrop 11a is to a circular shape, the higher the water repellency. As shown in FIG. 7, the shape of the raindrop 11a differs depending on whether the water repellency is high or low. Therefore, the shape of the raindrop 11a is analyzed, and it is determined that the larger the portion occupied by the arc in the outer diameter of the raindrop 11a, the higher the water repellency. For example, the ratio of the arc to the outer shape of the raindrop 11a is used as a coefficient, and if the coefficient is 1, the water repellency level is set to level 4 as an arc, that is, a circular shape. Further, it is determined that the closer the coefficient is to 0, the lower the water repellency level.

Further, as in the first embodiment described above, the behavior of the raindrop 11a adhering to the detection area 22 differs depending on the level of water repellency, so the level of water repellency is determined including the behavior of the raindrop 11a. When the raindrop 11a frequently moves from the detection area 22, that is, when the moving speed is high, it is determined that the water repellency is high, and when the raindrop 11a stays in the detection area 22, it is determined that the water repellency is low. Since the moving speed differs depending on the vehicle speed, it is determined that the water repellency is high when the moving speed is high at the same vehicle speed. For example, at the same vehicle speed, the moving speed is divided into four stages, and if the moving speed is the fastest, the water repellency level is determined to be level 4.

Further, the water repellency level can be determined more finely by determining the water repellency level obtained by adding the water repellency level determined by the outer shape of the raindrop 11a and the water repellency level determined by the moving speed of the raindrop 11a. In this case, it can be determined by eight levels of water repellency. For example, when the water repellency level determined by the shape of the raindrop 11a is level 4 and the water repellency level determined by the moving speed is level 3, the water repellency level is determined as level 7.

As described above, in the present embodiment, the in-vehicle control device 20 uses the shape of the imaged raindrop 11a as a parameter for determining water repellency. Therefore, the accuracy of determining water repellency can be further improved.

Further, in the present embodiment, the moving speed of the raindrop 11a is acquired from the captured image, and it is determined that the faster the moving speed of the raindrop 11a at the same vehicle speed, the higher the water repellency. Therefore, the accuracy of determining water repellency based on the behavior of the raindrop 11a can be improved.

The in-vehicle detection device 10 of the present embodiment is used for detecting the amount of raindrops, but is not limited to such a function, and for example, a drive recorder function of photographing the front of the vehicle 100 and recording the driving situation. It may be used together.

(Other embodiments)
Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and can be variously modified and implemented without departing from the gist of the present disclosure.

The structure of the above-described embodiment is merely an example, and the scope of the present disclosure is not limited to these descriptions. The scope of the present disclosure is indicated by the description of the scope of claims, and further includes all modifications within the meaning and scope equivalent to the description of the scope of claims.

The glass of the vehicle 100 is not limited to the windshield 11 in front of the vehicle 100, and may be the rear glass behind the vehicle 100. Further, the windshield is not limited to glass, and the windshield may be made of a translucent material and may be a plastic such as a thermoplastic.

In the first embodiment described above, the functions realized by the in-vehicle control device 20 may be realized by hardware and software different from those described above, or a combination thereof. The in-vehicle control device 20 may communicate with another control device, for example, and the other control device may execute a part or all of the processing. When the in-vehicle control device 20 is realized by an electronic circuit, it can be realized by a digital circuit including a large number of logic circuits or an analog circuit.

10 ... In-vehicle detection device (water-repellent detection device, raindrop amount acquisition unit, speed acquisition unit)
11 ... Windshield (Windshield) 11a ... Raindrop 12 ... Rain sensor 13 ... Solar sensor 14 ... Cover housing 15 ... Circuit board 16 ... Control unit (raindrop amount calculation unit) 17 ... Bracket 18 ... Connector 18a ... Terminal 19 ... Sheet 20 … In-vehicle control device (raindrop amount acquisition unit, speed acquisition unit)
21 ... Vehicle speed sensor 22 ... Detection area 23 ... Water repellency determination unit 30 ... Wiper device 31 ... Wiper switch 32 ... Wiper motor 33 ... Wiper blade 34 ... Link mechanism 41 ... Light emitting element (irradiation unit) 42 ... Light receiving element (light amount acquisition unit) )
43 ... Light guide lens unit 44 ... First lens unit 45 ... Second lens unit 51 ... Solar radiation detection element 52 ... Solar light guide unit 60 ... Imaging unit 100 ... Vehicle

Claims (5)

A water repellency detecting device for detecting the water repellency of the windshield (11) of the vehicle (100).
A raindrop amount acquisition unit (20) for acquiring the amount of raindrops adhering to the outer surface of the windshield, and
The speed acquisition unit (20) that acquires the speed of the vehicle and
A water repellency determining unit (23) for determining the degree of water repellency of the windshield based on the acquired transition of the amount of raindrops and the speed of the vehicle is included.
The water repellency determining unit is a water repellency detecting device that determines that the degree of water repellency is high when the amount of raindrops decreases as the vehicle speed increases. An irradiation unit (41) that irradiates light toward the inner surface of the windshield,
A light amount acquisition unit (42) that acquires the amount of reflected light of the light emitted toward the inner surface of the windshield, and a light amount acquisition unit (42).
A raindrop amount calculation unit (16) that calculates the amount of raindrops adhering to the outer surface of the windshield based on the light amount acquired by the light amount acquisition unit and outputs the calculation result to the raindrop amount acquisition unit is further included. The water repellent detection device according to claim 1. A water repellency detecting device for detecting the water repellency of the windshield (11) of the vehicle (100).
An imaging unit (60) that images the windshield and
A water repellency determining unit (23) for determining the degree of water repellency of the windshield based on the shape of the imaged raindrop is included.
The water repellency determining unit is a water repellency detecting device that determines that the closer the raindrop shape of the captured image is to a circular shape, the higher the water repellency. Further including a speed acquisition unit (20) for acquiring the speed of the vehicle,
The water repellency detecting device according to claim 3, wherein the water repellency determining unit calculates the moving speed of raindrops from the captured image, and determines that the faster the moving speed is, the higher the water repellency is at the same vehicle speed. The date and time when the windshield is given water repellency is set in advance.
The water repellency determining unit is one of claims 1 to 4, which corrects the water repellency to decrease as the operating time of the wiper device (30) for wiping raindrops on the windshield increases from the date and time of application. The water repellency detector described.

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